db_lock: new unified lock for songvec and dirvec

1 files changed, 55 insertions, 0 deletions

diff --git a/src/db_lock.h b/src/db_lock.h
new file mode 100644
index 000000000..1e557b985
--- /dev/null
+++ b/src/db_lock.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2003-2011 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/** \file
+ *
+ * Support for locking data structures from the database, for safe
+ * multi-threading.
+ */
+
+#ifndef MPD_DB_LOCK_H
+#define MPD_DB_LOCK_H
+
+#include "check.h"
+
+#include <glib.h>
+#include <assert.h>
+
+extern GStaticMutex db_mutex;
+
+/**
+ * Obtain the global database lock.  This is needed before
+ * dereferencing a #song or #directory.  It is not recursive.
+ */
+static inline void
+db_lock(void)
+{
+	g_static_mutex_lock(&db_mutex);
+}
+
+/**
+ * Release the global database lock.
+ */
+static inline void
+db_unlock(void)
+{
+	g_static_mutex_unlock(&db_mutex);
+}
+
+#endif